Throttle control assembly with integrated safety switch

ABSTRACT

A throttle control assembly includes a cable lever, a switch assembly, a throttle control device, and a switch engagement surface. The cable lever is adapted for coupling to a throttle cable and is configured, upon receipt of a drive torque, to rotate. The switch assembly is coupled to the cable lever and includes a switch that is movable between a first position and a second position. The throttle control device has the switch engagement surface formed on a portion of its inner surface. The switch engagement surface is configured, upon rotation of the throttle control device, to selectively move the switch between the first position and the second position and selectively rotate the switch assembly to thereby supply the drive torque to the cable lever.

TECHNICAL FIELD

The present invention generally relates to throttle control devices, andmore particularly relates to a throttle control assembly that includesan integrated safety switch.

BACKGROUND

Many recreational vehicles, such as, for example, all-terrain vehicles(ATVs) and snowmobiles, include a throttle control that is manipulatedby an operator's hand and, more particularly, by the thumb on one of theoperator's hands. These types of throttle controls are typically coupledto a throttle cable that, when manipulated via the throttle control,varies the flow of fuel and/or air to the engine, thereby controllingthe acceleration and speed of the vehicle.

Although presently known throttle controls, such as the one describedabove, are generally safe and reliable, these controls can exhibitcertain drawbacks. For example, if certain postulated throttle cablemalfunctions were to occur, the throttle control may not allow anoperator to sufficiently control the speed and/or acceleration of thevehicle. These postulated malfunctions include both a broken throttlecable and a stuck throttle cable.

Hence, there is a need for a throttle control that will allow anoperator to sufficiently control the speed and/or acceleration of avehicle if a postulated throttle cable malfunction occurs. The presentinvention addresses at least this need.

BRIEF SUMMARY

In one embodiment, a throttle control assembly includes a cable lever, aswitch assembly, a throttle control device, and a switch engagementsurface. The cable lever is adapted for coupling to a throttle cable.The cable lever is configured to receive a drive torque and, uponreceipt of the drive torque, to rotate. The switch assembly is coupledto the cable lever and is configured to selectively rotate and supplythe drive torque to the cable lever. The switch assembly includes aswitch that is movable between a first position and a second position.The throttle control device is configured to rotate about an axis, andhas an outer surface and an inner surface. The outer surface has a thumblever extending outwardly therefrom, and the inner surface defines anopening within which at least a portion of the switch assembly isdisposed. The switch engagement surface is formed on a portion of theinner surface of the throttle control device and is configured, uponrotation of the throttle control device, to selectively move the switchbetween the first position and the second position and selectivelyrotate the switch assembly to thereby supply the drive torque to thecable lever.

In another embodiment, a throttle control assembly includes a cablelever, a switch assembly, a throttle control device, a spring, and aswitch engagement surface. The cable lever is adapted for coupling to athrottle cable. The cable lever is configured to receive a drive torqueand, upon receipt of the drive torque, to rotate. The switch assembly iscoupled to the cable lever and is configured to selectively rotate andsupply the drive torque to the cable lever. The switch assembly includesa switch housing, a switch that is disposed at least partially withinthe switch housing and is movable between a first position and a secondposition, and a cable lever axle that is coupled to the switch housingand the cable lever. The throttle control device is configured to rotateabout an axis between a minimum throttle position and a maximum throttleposition, and has an outer surface and an inner surface. The outersurface has a thumb lever that extends outwardly therefrom, and theinner surface defines an opening within which at least a portion of theswitch assembly is disposed. The spring is coupled to the throttlecontrol device and the switch assembly. The spring supplies a bias forcethat biases the throttle control device toward the minimum throttleposition. The switch engagement surface is formed on a portion of theinner surface of the throttle control device and is configured, uponrotation of the throttle control device, to selectively engage theswitch assembly, to thereby selectively rotate and supply the drivetorque to the cable lever, and selectively move the switch between thefirst position and the second position.

In still another embodiment, a throttle control assembly includes acable lever, a throttle control device, a thumb lever, a switch, and aswitch engagement surface. The cable lever is adapted for coupling to athrottle cable. The cable lever is configured to receive a drive torqueand, upon receipt of the drive torque, to rotate. The throttle controldevice is coupled to the cable lever and is configured to rotate aboutan axis and supply the drive torque to the cable lever. The thumb leveris rotationally coupled to, and extends outwardly from, the throttlecontrol device. The thumb lever is configured, upon application of aforce in a first direction, to cause the throttle control device torotate. The switch is coupled to the throttle control device and ismovable between a first position and a second position. The switchengagement surface is formed on a portion of the thumb lever and isconfigured, upon application of a force to the thumb lever, toselectively move the switch between the first position and the secondposition.

Furthermore, other desirable features and characteristics of thethrottle control assembly will become apparent from the subsequentdetailed description and the appended claims, taken in conjunction withthe accompanying drawings and the preceding background.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will hereinafter be described in conjunction withthe following drawing figures, wherein like numerals denote likeelements, and wherein:

FIG. 1 depicts a simplified functional block diagram of a vehicle;

FIGS. 2 and 3 depict a partial cross section view and an exploded view,respectively, of an embodiment of a throttle control assembly that maybe used with the vehicle of FIG. 1;

FIGS. 4 and 5 depict close-up cross section and bottom views of thethrottle control assembly depicted in FIGS. 2 and 3; and

FIGS. 6 and 7 depict plan views and bottom view, respectively, of analternative embodiment of a throttle control assembly.

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and isnot intended to limit the invention or the application and uses of theinvention. As used herein, the word “exemplary” means “serving as anexample, instance, or illustration.” Thus, any embodiment describedherein as “exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments. All of the embodiments describedherein are exemplary embodiments provided to enable persons skilled inthe art to make or use the invention and not to limit the scope of theinvention which is defined by the claims. Furthermore, there is nointention to be bound by any expressed or implied theory presented inthe preceding technical field, background, brief summary, or thefollowing detailed description.

Referring to FIG. 1, a simplified functional block diagram of a vehicle100 is depicted. The depicted vehicle 100 includes, among various othernon-illustrated components, an engine 102, a throttle control assembly104, and an engine control unit (ECU) 106. The engine 102, at least inthe depicted embodiment, is a gas-powered, internal combustion engine.The rotational speed of the engine 102, and thus the speed andacceleration of the vehicle 100, is varied by controlling the flow rateof air into the engine 102, and thus the fuel/air ratio.

The flow rate of air into the engine 102 is controlled via the throttlecontrol assembly 104. In the depicted embodiment, the throttle controlassembly 104, an embodiment of which will be described in more detailfurther below, controls the flow rate of air by varying the position ofa throttle valve 108. To do so, the throttle control assembly 104, whichis disposed remote from the throttle valve 108, is coupled to thethrottle valve 108 via a throttle cable 112. An operator of the vehicle100 may position the throttle valve 108, and thus control the speed andacceleration of the vehicle 100, by manually positioning the throttlecontrol assembly 104.

The ECU 106 is coupled to receive various sensor signals from various,non-illustrated sensors disposed within the engine 102 and/or otherlocations on the vehicle 100. These sensors may include, but are notlimited to, a throttle position sensor, a speed sensor, and atemperature sensor, just to name a few. As will be described in moredetail further below, the ECU 106 also receives a switch position signal114 from the throttle control assembly 104. The ECU 106 is coupled toreceive the sensor signals and the switch position signal and isconfigured, in response to these signals, to control the operationalmode of the engine 102. For example, the ECU 106 may control the engine102 to operate in a “normal” mode, in which engine speed is controlledvia the throttle control assembly 104. The ECU 106 may also control theengine 102 to operate in a “limited” operational mode, in which thespeed of the engine 102 is limited to a relatively low speed. In someinstances the ECU 106 may cause the engine 102 to completely shut down.

With reference now to FIGS. 2 and 3, a partial cross section view and anexploded view, respectively, of an embodiment of the throttle controlassembly 104 are depicted. The depicted throttle control assembly 104includes a cable lever 202, a switch assembly 204, and a throttlecontrol device 206. The cable lever 202 is coupled to the throttle cable112. The cable lever 202 is also coupled to receive a drive torque andis configured, upon receipt of the drive torque, to rotate.

The switch assembly 204 is coupled to the cable lever 202 and isconfigured to selectively rotate and supply the drive torque to thecable lever 202. The switch assembly 202 may be variously configured andimplemented, but in the depicted embodiment it includes a switch housing208, a cable lever axle 212, and a switch 214. The switch housing isdisposed within an opening 216 formed in the throttle control device206. The cable lever axle 212 extends from the opening 216 of thethrottle control device 206, and is coupled to both the switch housing208 and the cable lever 202. In the depicted embodiment, the cable leveraxle 212 is coupled to the switch housing 208 via a fastener 209, and ispress-fit into an opening in the cable lever 202.

The switch 214 is disposed within the switch housing 208 and is movablebetween a first position and a second position, and is configured, whenproperly connected, to supply the switch position signal 114 to the ECU106. The first and second positions may be, for example, an “open”position and a “closed” position, respectively, or a “closed” positionand an “open” position, respectively. Alternatively, the first andsecond positions may be positions that simply vary the magnitude of theswitch position signal 114. In the depicted embodiment, however, thefirst position corresponds to an “open” position, and the secondposition corresponds to a “closed” position. Although the switch 214 maybe variously configured and implemented, it is preferably has at leastan IP (ingress protection) rating of 67 (e.g., IP67). Moreover, althoughthe depicted switch 214 is implemented using a tact switch, it couldalso be implemented using any one of numerous suitable switchesincluding, for example, a reed switch or a snap acting switch, just toname a few.

The throttle control device 206 is configured to rotate about an axis218, and includes an outer surface 222 and an inner surface 224. Theouter surface 222 has a thumb lever 226 extending outwardly therefrom,and the inner surface 224 defines the opening 216 within which at leasta portion of the switch assembly 204 is disposed. The throttle controldevice 206 is rotatable, about the axis 218, between a minimum throttle(or idle) position and a maximum throttle position. As FIG. 3 depictsmore clearly, the throttle control assembly 104 additionally includes aspring 302. The spring 302 is coupled to the throttle control device 206and the switch assembly 204, and supplies a bias force that biases thethrottle control device 206 toward the minimum throttle position. Thepurpose for this will become apparent further below.

Referring now to FIGS. 4 and 5, it is seen that a switch engagementsurface 402 is formed on a portion of the inner surface 224 of thethrottle control device 206. The switch engagement surface 402 isconfigured, upon rotation of the throttle control device 206, toselectively move the switch 208 between the first position and thesecond position. The switch engagement surface 402 is additionallyconfigured, upon rotation of the throttle control device 206, toselectively rotate the switch assembly 204 to thereby supply the drivetorque to the cable lever 202. The manner in which this functionality isachieved will now be described.

The throttle control assembly 104 is configured such that the throttlecontrol device 206 is rotatable relative to the switch housing 208. Withthis configuration, when the throttle control device 206 is in theminimum throttle position, which is the position depicted in FIGS. 4 and5, the switch engagement surface 402 does not actuate the switch 214 norcause rotation of the switch assembly 204. However, when the throttlecontrol device 104 is rotated a predetermined amount out of the minimumthrottle position and toward the maximum throttle position, the switchengagement surface 402 actuates the switch 214, thereby moving it fromthe first position to the second position, and engages the switchhousing 208, thereby causing rotation of the switch assembly 204. Itshould be noted that in the depicted embodiment, the switch engagementsurface 402 is configured such that, upon rotation of the throttlecontrol device from the minimum throttle position toward the maximumthrottle position, it moves the switch 214 to the first position beforeit rotates switch assembly 204.

Having described the structural features and the overall function of thethrottle control assembly 104, a more detailed description of itsoperation will now be described. Initially, it is assumed that thethrottle control device 204 is in the minimum throttle position.Thereafter, as user initially applies a force to the thumb lever 226,the throttle control device 206 will rotate, against the bias force ofthe spring 302 and relative to the switch housing 208, out of theminimum throttle position. When the throttle control device 206 isrotated to the predetermined position, the switch engagement surface 402moves the switch 214 from the first position to the second position,supplying the switch signal 114 to the ECU 106 indicating that thethrottle control assembly 104 is initiating engine speed control. As thethrottle control device 206 is rotated beyond this position, it causesthe switch assembly 204 to rotate, which in turn causes the cable lever202 to rotate. Rotation of the cable lever 202 supplies a force to thethrottle cable 112, which in turn positions the throttle valve 108.

As previously noted, it is postulated that certain unlikely events mayoccur during vehicle operation. One such unlikely event is a brokenthrottle cable 112. If this unlikely, yet postulated event were tooccur, the bias force supplied by the spring 302 would generate relativemotion between the throttle control device 206 and the cable lever 202,and thus also the switch assembly 204. As such, the switch engagementsurface 402 would no longer engage the switch 214, and the switch 214would return to the second position. This would thus signal this eventto the ECU 106.

Another unlikely, yet postulated event is a stuck throttle cable 112. Ifthis were to occur, the user would feel a relatively high resistance tothe otherwise easy actuation of the throttle control device 206. Inresponse, the user may then release the thumb lever 202. Here again, thebias force supplied by the spring 302 would generate relative motionbetween the throttle control device 206 and the cable lever 202, andthus also the switch assembly 204. As such, the switch engagementsurface 402 would no longer engage the switch 214, and the switch 214would return to the second position. This would thus signal this eventto the ECU 106.

The throttle control assembly 104 depicted in FIGS. 2-5 is merelyexemplary of one particular embodiment. Another exemplary embodiment isdepicted in FIGS. 6 and 7, and includes cable lever 602, a throttlecontrol device 604, a thumb lever 606, a switch 608, and a switchengagement surface 612. The cable lever 602 is coupled to the throttlecable 112. The cable lever 602 is also coupled to receive a drive torqueand is configured, upon receipt of the drive torque, to rotate.

The throttle control device 604 is coupled to the cable lever 602 and isconfigured to rotate about an axis 614 and supply the drive torque tothe cable lever 602. The thumb lever 606 is rotationally coupled to, andextends outwardly from, the throttle control device 604. The thumb lever606 is configured, upon application of a force in a first direction 616,to cause the throttle control device 604 to rotate about the axis 614.

The switch 608 is coupled to the throttle control device 604 and ismovable between a first position and a second position. As with thepreviously described embodiment, the switch 608 is configured, whenproperly connected, to supply the switch position signal 114 to the ECU106. The first and second positions may be, for example, an “open”position and a “closed” position, respectively, or a “closed” positionand an “open” position, respectively. Alternatively, the first andsecond positions may be positions that simply vary the magnitude of theswitch position signal 114. In the depicted embodiment, however, thefirst position corresponds to an “open” position, and the secondposition corresponds to a “closed” position.

Unlike the other embodiment, the switch engagement surface 612 of thisembodiment is formed on a portion of the thumb lever 606. Similar to theother embodiment, however, the switch engagement surface 612 isconfigured, upon application of a force to the thumb lever 606, toselectively move the switch 608 between the first position and thesecond position.

The embodiments described herein provide significant advantages overcurrent throttle control assemblies. The switch is preferably at leastan IP67 rated switch, and is thus sealed for reliability. The switch isintegrated into throttle control device thereby reducing the number ofwires and parts, and thus the complexity, relative to existing products.

Those of skill in the art will appreciate that the various illustrativelogical blocks, modules, circuits, and algorithm steps described inconnection with the embodiments disclosed herein may be implemented aselectronic hardware, computer software, or combinations of both. Some ofthe embodiments and implementations are described above in terms offunctional and/or logical block components (or modules) and variousprocessing steps. However, it should be appreciated that such blockcomponents (or modules) may be realized by any number of hardware,software, and/or firmware components configured to perform the specifiedfunctions. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted as causing adeparture from the scope of the present invention. For example, anembodiment of a system or a component may employ various integratedcircuit components, e.g., memory elements, digital signal processingelements, logic elements, look-up tables, or the like, which may carryout a variety of functions under the control of one or moremicroprocessors or other control devices. In addition, those skilled inthe art will appreciate that embodiments described herein are merelyexemplary implementations

The various illustrative logical blocks, modules, and circuits describedin connection with the embodiments disclosed herein may be implementedor performed with a general purpose processor, a digital signalprocessor (DSP), an application specific integrated circuit (ASIC), afield programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The steps of a method or algorithm described in connection with theembodiments disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of storage medium known in the art. Anexemplary storage medium is coupled to the processor such the processorcan read information from, and write information to, the storage medium.In the alternative, the storage medium may be integral to the processor.The processor and the storage medium may reside in an ASIC. The ASIC mayreside in a user terminal. In the alternative, the processor and thestorage medium may reside as discrete components in a user terminal.

In this document, relational terms such as first and second, and thelike may be used solely to distinguish one entity or action from anotherentity or action without necessarily requiring or implying any actualsuch relationship or order between such entities or actions. Numericalordinals such as “first,” “second,” “third,” etc. simply denotedifferent singles of a plurality and do not imply any order or sequenceunless specifically defined by the claim language. The sequence of thetext in any of the claims does not imply that process steps must beperformed in a temporal or logical order according to such sequenceunless it is specifically defined by the language of the claim. Theprocess steps may be interchanged in any order without departing fromthe scope of the invention as long as such an interchange does notcontradict the claim language and is not logically nonsensical.

Furthermore, depending on the context, words such as “connect” or“coupled to” used in describing a relationship between differentelements do not imply that a direct physical connection must be madebetween these elements. For example, two elements may be connected toeach other physically, electronically, logically, or in any othermanner, through one or more additional elements.

While at least one exemplary embodiment has been presented in theforegoing detailed description of the invention, it should beappreciated that a vast number of variations exist. It should also beappreciated that the exemplary embodiment or exemplary embodiments areonly examples, and are not intended to limit the scope, applicability,or configuration of the invention in any way. Rather, the foregoingdetailed description will provide those skilled in the art with aconvenient road map for implementing an exemplary embodiment of theinvention. It being understood that various changes may be made in thefunction and arrangement of elements described in an exemplaryembodiment without departing from the scope of the invention as setforth in the appended claims.

What is claimed is:
 1. A throttle control assembly, comprising: a cablelever adapted for coupling to a throttle cable, the cable leverconfigured to receive a drive torque and configured, upon receipt of thedrive torque, to rotate; a switch assembly coupled to the cable leverand configured to selectively rotate and supply the drive torque to thecable lever, the switch assembly including a switch that is movablebetween a first position and a second position; a throttle controldevice configured to rotate about an axis, the throttle control devicehaving an outer surface and an inner surface, the outer surface having athumb lever extending outwardly therefrom, the inner surface defining anopening within which at least a portion of the switch assembly isdisposed; and a switch engagement surface formed on a portion of theinner surface of the throttle control device and configured, uponrotation of the throttle control device, to (i) selectively move theswitch between the first position and the second position and (ii)selectively rotate the switch assembly to thereby supply the drivetorque to the cable lever.
 2. The assembly of claim 1, wherein: thethrottle control device is rotatable between a minimum throttle positionand a maximum throttle position; and the assembly further comprises aspring coupled to the throttle control device and the switch assembly,the spring supplying a bias force that biases the throttle controldevice toward the minimum throttle position.
 3. The assembly of claim 2,wherein: the switch engagement surface does not engage the switchassembly when the throttle control device is in the minimum throttleposition; and the switch engagement surface engages the switch assemblywhen the throttle control device is rotated a predetermined amounttoward the maximum throttle position.
 4. The switch assembly of claim 3,wherein the switch engagement surface is configured, upon rotation ofthe throttle control device from the minimum throttle position towardthe maximum throttle position, such that it moves the switch to thefirst position before it rotates switch assembly.
 5. The assembly ofclaim 1, wherein the switch assembly further comprises: a switch housingdisposed within the opening of the throttle control device, the switchdisposed within the switch housing; a cable lever axle coupled to theswitch housing and the cable lever, the cable lever axle extending fromthe opening of the throttle control device.
 6. The assembly of claim 5,wherein the throttle control device is rotatable relative to the switchhousing.
 7. The assembly of claim 6, wherein the throttle control devicedoes not rotate the switch assembly until the switch engagement surfaceengages the switch housing.
 8. A throttle control assembly, comprising:a cable lever adapted for coupling to a throttle cable, the cable leverconfigured to receive a drive torque and configured, upon receipt of thedrive torque, to rotate; a switch assembly coupled to the cable leverand configured to selectively rotate and supply the drive torque to thecable lever, the switch assembly including a switch housing, a switchdisposed at least partially within the switch housing and movablebetween a first position and a second position, and a cable lever axlecoupled to the switch housing and the cable lever; a throttle controldevice configured to rotate about an axis between a minimum throttleposition and a maximum throttle position, the throttle control devicehaving an outer surface and an inner surface, the outer surface having athumb lever extending outwardly therefrom, the inner surface defining anopening within which at least a portion of the switch assembly isdisposed; a spring coupled to the throttle control device and the switchassembly, the spring supplying a bias force that biases the throttlecontrol device toward the minimum throttle position; and a switchengagement surface formed on a portion of the inner surface of thethrottle control device and configured, upon rotation of the throttlecontrol device, to (i) selectively engage the switch assembly, tothereby selectively rotate and supply the drive torque to the cablelever, and (ii) selectively move the switch between the first positionand the second position.
 9. The assembly of claim 8, wherein: the switchengagement surface does not engage the switch assembly when the throttlecontrol device is in the minimum throttle position; and the switchengagement surface engages the switch assembly when the throttle controldevice is rotated a predetermined amount toward the maximum throttleposition.
 10. The assembly of claim 8, wherein the throttle controldevice is rotatable relative to the switch housing.
 11. The assembly ofclaim 10, wherein the throttle control device does not rotate the switchassembly until the switch engagement surface engages the switch housing.12. A throttle control assembly, comprising: a cable lever adapted forcoupling to a throttle cable, the cable lever configured to receive adrive torque and configured, upon receipt of the drive torque, torotate; a throttle control device coupled to the cable lever andconfigured to rotate about an axis and supply the drive torque to thecable lever; a thumb lever rotationally coupled to, and extendingoutwardly from, the throttle control device, the thumb lever configured,upon application of a force in a first direction, to cause the throttlecontrol device to rotate; a switch coupled to the throttle controldevice and movable between a first position and a second position; and aswitch engagement surface formed on a portion of the thumb lever andconfigured, upon application of a force to the thumb lever, toselectively move the switch between the first position and the secondposition.